package com.lbc.add;

import java.sql.Time;
import java.util.concurrent.Semaphore;
import java.util.concurrent.TimeUnit;

public class SemaphoreDemo {
    public static void main(String[] args) {
        //  线程数量: 停车位！限流！
        Semaphore semaphore = new Semaphore(3);

        for (int i = 1; i <=6; i++) {
            new Thread(()->{
                //  acquire()  等待
                try {
                    semaphore.acquire();
                    System.out.println(Thread.currentThread().getName()+"抢到车位");
                    TimeUnit.SECONDS.sleep(2);
                    System.out.println(Thread.currentThread().getName()+"离开车位");
                } catch (InterruptedException e) {
                    e.printStackTrace();
                } finally {
                    semaphore.release();  //  释放
                }
            },String.valueOf(i)).start();
        }

    }
}
